Lens for DSLR video shoot

ikas

I am a beginner to photography. I am planning to do a very specific type of video shoot over a couple of months. The subject is going to be human. Subject would occupy not more than 1/5th to 1/3rd of the height of the video frame height because lot of background to the left, right and back of the subject needs to be captured. The subject and immediate area surrounding the subject need to be as sharp as possible. The goal is to get as clear a view of the face as the subject occupies only a little portion of the frame. From the very little of what I know, I think this is what I might need to do:

- Shoot as low an ISO as possible.
- Shoot as high a shutter speed as possible (to avoid motion blur and to get crisp contrasted subjects).
- Get better dynamic range which can in turn help me have the subject looking better and sharper.

What kind of lens should I go for? Would a f/1.2lens work better than a f/2.8 lens?
I have a T3i and Canon 50mm f/1.4 lens. How much of an improvement (lower ISO, increased shutter speed, better dynamic range) can I get if I upgrade to an L? How much of an improvement can I get if I upgrade to a full frame?

@Moose I really like the design of this site. @Moose and @PBKed I have tried to gather answers to my question from many of your comments to other discussions, but have not been able to reach a conclusion.

PBked

Hi Ikas,
I think the solutions you have listed are correct. However, I am trying to decide what kind of video you are wanting to produce. By that I mean what is the importance of the subject in your frame? From your description, it would seem that it is not the human, but then in your scenario, it is not the background either.
If I was attempting something like this, I would be tempted to place my subject to one side and fill the frame from top to bottom with him. In video mode, I would then pan and maybe zoom to take in the background. This way, both the human subject and the background are given a share of the importance and focus. If you watch news reports you will see this technique being used all the time. The brain, thanks to our eyes, needs to have something predominant to focus on. With your scenario, where is the focus?
On the technical side, you are going to need as much depth of field as possible using something between f/8 and f/16. Larger aperture lenses such as f/1.2 or f/2.8 have limited depth of field.
If you can afford it, L glass is always the way to go. Full frame does not benefit video as much as it does static photography. Your T3i is capable for the job.
Hope this has given you some food for thought.
Best regards,
PBked

ikas

Thanks, @PBked.

The reason I need the primary subject, the human, to be under 1/3rd the height of the video frame is for three reasons:
1) there are going to be some tall props and objects of interest kept around the subject that need to be completely visible and in focus.
2) there is going to be some post done on the video that will have basic animation and cartoon added to it.
3) to track in post, the sharper the image and objects, the better it is.

Regarding the body, I was under the impression that moving to a full frame would get me advantages of better ISO and better tonal range than my T3i. I guess then it doesn't hold good for video.

On the lens I have quite some confusion. In what way would upgrading to an L benefit video? I understand all lenses allow shooting focus to infinity. So would a f/1.2 lens when focused to infinity shoot at a larger aperture compared to a f/2.8 lens focused to infinity ? Am I totally off the mark on this one? Would a parfocal lens and shooting at hyperfocal length be relevant and useful to this scenario?

This is a hobby project of mine and I am doing it when time permits.

PBked

Hi again,
I think I am stupid because I still cannot see how reducing the human to 1/3 the height of the frame will make him the primary subject. But hey, this is your video and you have obviously given it a lot of thought.
I'm not suggesting you buy L quality glass, but it provides you with the best optical and tonal quality.
A f/1.2 is an f/1.2 wherever it is focussed. The problem remains the same in that you will not achieve a very great depth of field. The benefits of large aperture lenses are their better low light capability and their ability to achieve good bokeh (blurry backgrounds). Smaller apertures equal more depth of field (f/8-f/16).
The best ISO for quality is around 100 (some cameras can drop to 60 or 80 which is even better), so a full frame does not give you a better ISO just a bigger range. As for video, 1080 quality is the same whether on a full frame or not. Your T3i is more than able.
If you really want to specialize in video, then invest in a good video camera, not a DSLR.
Good luck with your hobby and your video project.
Regards,
PBked

ikas

Thank you @PBked for clearing that up. One of the reasons I am considering a DSLR is that I can invest in a quality lens and use the gear I already have. I have a Panasonic TM700 that shoots at 60 fps and allows manual control. But I am at a loss how to compare the lens of camcorder to that of an L lens. I never have explored professional video cameras as my budget is below $3k.

Best Regards,
Ikas

PBked

Hi Ikas,
Points taken. I suggest you save towards an L series lens. You will be getting the best quality there is, and if you stick with Canon the lens will always be transferable. I tend to advise your money be spent on lenses rather than the body.
Best regards,
PBked

Moose

@ikas - I'd love to give you better instruction, but unfortunately I'm still very green when it comes to capturing HD video. I would ask @amigo in the Canon T3i forum. He's got some experience with video recording, recommended settings, etc...

I appreciate the kind comments and welcome to the forum. :)

amigo

@ikas,

Here are my random thoughts. The subject is going to be human and would occupy not more than 1/5th to 1/3rd of the height of the video frame height. What's your target audience? How will they be viewing your film (on a theater screen, on a 60 inch TV, on a computer monitor using Vimeo or YouTube, on a mobile device)? If the answer is a mobile device, your subject will be hard to see on such a small screen.
Are you shooting outdoors or indoors? Day or night? There are going to be some tall props and objects of interest kept around the subject that need to be completely visible and in focus. The subject and immediate area surrounding the subject need to be as sharp as possible. The goal is to get as clear a view of the face as the subject occupies only a little portion of the frame. Will these things be moving a lot or be relatively still? High shutter speed to reduce motion blur is not necessary if things are standing still or moving slowly. Also, viewers over the years have been accustomed to 24 frames per second, and you should use a 1/50th of a second shutter speed with that frame rate. If the shutter is too fast there isn’t enough motion blur to smoothly transition from frame to frame causing a stuttering or staccato effect:



Another downside of a high shutter speed is that you need to open the lens wider in order to get the correct exposure (you want enough light in). When you get the lens wide open, say f/1.8 or f/1.4, then the range of things that are in focus (depth of field) is much shallower, thereby making your goal of having multiple things around your subject in sharp focus that much more difficult. Like PBked wrote, if you have sufficient lighting, I would aim for a smaller aperture, f/8, f/11 or even f/16. This way you will have more things in focus and you will make life a lot easier for yourself when it comes to pulling focus. So what we're saying is there is no advantage to using an f/1.2 lens, because you will be using an aperture of f/5.6 or higher anyway.

http://www.lensrentals.com/blog/2009/04/controlling-depth-of-field

Shoot as low an ISO as possible. With the T3i, filming in neutral style when things are properly exposed can yield excellent results up to ISO 800, and I have produced acceptable videos at ISO 1600. High ISO sucks in low light, but not as much in brightly lit scenes.

Regarding the body, I was under the impression that moving to a full frame would get me advantages of better ISO and better tonal range than my T3i. I guess then it doesn't hold good for video.

Yes you would get greater dynamic range by using a full frame camera. You'd also get better results using a $65,000 Arri Alexa camera. In reality, you don't need a full frame camera to produce great looking films, especially if this is only a hobby project. Sure you could purchase very expensive lenses and improve the image quality somewhat, but the story you tell is more important than the equipment. Just watch this short film which was shot using a Canon 7D (same sensor and same image quality as the T3i) and a couple of old Nikon lenses and see what's possible on a limited budget:



Anyway if you want incredible lenses, my favorite one is the Zeiss Distagon 35mm f/1.4. Since I can't rationalize its purchase (yet), I rent it. At my local camera store, I can rent this $1800 lens for $35 per weekend. That lens is manual focus only, but that's fine because DSLR filmmaking is all about manual focus anyway. This lens has incredible sharpness, contrast and colors. It has a big, smooth focus ring. It blows me away and I can't say enough good things about it.

If you want things to look flat and unidimensional, you can take a 100mm lens from farther away. If you want more perspective, you can use a 50mm positioned closer to get the same things within the frame, but with more perspective. In all cases, you should mount your camera on a tripod; this will help with sharpness. Handheld is fine in bright daylight with a lens equipped with IS (image stabilization) provided you are proficient at holding the camera still and moving smoothly, otherwise people will quickly develop nausea watching your footage. If you have some money left, you could invest in a good microphone and digital sound recorder. It's better to have great quality sound and APS-C video than full frame footage with the crappy onboard microphone sound. I use a rode NTG-2 microphone hooked up to a Zoom H4N digital audio recorder, and I synch the sound and video clips using Sony Vegas.

I apologize for the rather lengthy answer. I hope it will be useful to you.

ikas

Thanks @Moose for introducing @amigo to the discussion.

@PBKed I will keep those points in mind, but which lens? I realize there is no one size fits all lens, so I'm trying to understand what might be best for my project. There are cine lenses, L lenses, FD lenses, parfocal lenses and tilt shift lenses.

@amigo I really appreciate the detailed answer. There is no specific target audience. It's a general work of art with a message kind of video targeted at the casual browser. The distribution medium is going to be internet and played on computers. Its going to be HD. My current plan is to shoot outdoors at daytime. I would love to do it indoors, but getting sufficient lighting to cover a large area may not be in budget.
The props are not going to be moving, but the subject is going to be. It's not fast action or sports, just casual walk and body motions.

I happened to watch that exact same video couple of days back to understand the stuttering or staccato effect. It's very useful.

Since there is there is no advantage to using an f/1.2 lens, because I'll be using an aperture of f/5.6 or higher anyway, would an f/8 hold good on overcast cloudy days? Given that I am planning for the height restriction of the subject, wouldn't the choice of lens affect how far away from the subject I would need to be?

I agree the story and audio is important. I want to get the visual part correct as I don't have much information on it. I believe my rather strange looking requirement of 1/3rd height of subject is going to enhance and support the story, narrative and subject. I would like to get the look right.

I will see if I can get the Zeiss Distagon 35mm f/1.4 to try it out. I am temporarily located in Maine and I'm not sure where I can rent one. Are there any online rentals that I can check out or is it better to rent from a local store?

In regards to your comment "If you want things to look flat, unidimensional, you can take a 100mm lens from farther away, and if you want more perspective, you can use a 50mm positioned closer to get the same things within the frame, but with more perspective" what's perspective ? What's the difference between more perspective versus less perspective? Would there be any videos you could link to show the effect like the one for the stuttering effect ? Could you link to examples that show a flat and unidimensional versus a depth and multidimensional look?

I have the H4n, but not decided on the mic yet.

@Moose, as I progress forward over the next months, would it be better to post my questions on this thread or post a new one depending on the topic?

Thanks again everybody for all the answers.

amigo

Hello @ikas,

> Would an F/8 hold good on overcast cloudy days ?

For proper exposure, you basically have 3 settings you can play with; aperture, shutter speed and ISO. Shutter speed you'll set at around 1/50th of a second, and that will pretty much stay there; aperture depends on the depth of field you are looking for. In daylight, unless the clouds are very dark, you should be fine at f/8. As you set a higher aperture number fF/8, f11 or beyond), the amount of light that reaches the camera sensor diminishes correspondingly. In order to retain a proper exposure, you will gradually increase the ISO setting. Just try to stay below ISO 1600, ideally not more than ISO 800. On the set, while preparing your shot, perform some tests and check them out on a monitor, HDTV, or laptop, to verify that you have proper exposure and focus.

> Is there any online rentals that I can check out, or is it better to rent from a local store?
http://www.lensrentals.com.

If you can rent from a local store that's not too far away, you'll save the shipping costs. Plus you'll be helping the local economy.

> Could you link to examples that show a flat and unidimensional versus a depth and multidimensional look?

The first photo has a 12mm focal length. The bridge appears to be far away. Call it deep perspective. The third picture is 100mm, the bridge appears to be very close to the subject. The perspective is crushed, and the various items in the picture almost appear to be on the same plane:

http://photo.tutsplus.com/tutorials/photography-fundamentals/exploring-how-focal-length-affects-images/

Also see this video, especially at 4:10

ikas

Thank you for the answers @amigo.